1. Field of the Invention
The present invention relates to an airbag device attached to a roof side rail of a vehicle.
2. Description of Related Art
A vehicle airbag device in which an airbag is deployed in a curtain form from a roof side rail of the vehicle in order to prevent the head portion of an occupant from colliding with a side window or the like in the event of a side crash is known. Such an airbag device is also referred to as a curtain airbag device.
In a curtain airbag device, an airbag is folded in a long and thin manner and is stored in a protective cover that is attached to a roof side rail of a vehicle. Airbags and protective covers are often disposed along the entire roof side rail in a front-rear direction of a vehicle in order to protect an occupant on a rear seat as well as an occupant on a front seat.
As a result, since the entire protective cover is long, it is not desirable to form the protective cover as an integral body when transportation or the like before attachment to a vehicle is taken into consideration. Thus, Japanese Patent Application Publication No. 2011-31640 proposes an airbag device in which a protective cover is divided along a longitudinal direction into a plurality of parts so that the protective cover can be bent in a compact form.
In an airbag device in which a protective cover is divided, an airbag folded in a long and thin manner is stored and protected by a plurality of protective covers disposed in line in a longitudinal direction of the airbag.
In general, an airbag is formed from a fabric or the like that can be deformed flexibly. Thus, before an airbag device is attached to a vehicle, the respective protective covers may rotate about the longitudinal direction of the airbag and the airbag stored therein may be twisted. That is, the respective protective covers may be attached to a vehicle in a state where the airbag stored therein is twisted erroneously.
If protective covers are attached to a vehicle in a state where the airbag is twisted, the airbag may not be deployed properly between an occupant and a side window or the like in the event of a crash and may be unable to protect the occupant. Besides this, a dangerous situation may occur.
Thus, in the airbag device disclosed in Japanese Patent Application Publication No. 2011-31640, a connecting mechanism that connects adjacent two protective covers so that the protective covers cannot rotate in relation to each other is provided in an end of each protective cover.